The present invention relates to a hand-held device for connection to a control unit designed as a tripping device of an electronic device such as a circuit breaker or motor drive. The control unit has a programmable memory circuit for storing performance characteristics. The hand-held device also has a display device for display of performance characteristics transmitted to the hand-held device from the control unit by a transmission arrangement and is provided with a microprocessor circuit and an electronic data storage to store the performance characteristics transmitted from the control unit.
A conventional hand-held device is described in U.S. Pat. No. 4,751,605. In conjunction with circuit breakers, a transmission of data from the control units to the hand-held terminal is provided to simplify the electronic overcurrent trip units of the circuit breakers by providing only one hand-held terminal for displaying the set parameters of multiple circuit breakers. There are no provisions for transmitting data in the opposite direction.
Furthermore, U.S. Pat. No. 4,272,816 describes a setting aid for the tripping curve of a switching device of a circuit breaker. The setting aid has the form of a matrix arrangement of plug-in orifices for programming pins. This limits the function of the setting aid to setting a tripping characteristic curve of a microcomputer of the protective device.
An object of the present invention is to provide a hand-held terminal with expanded functions, so that it can be used not only for circuit breakers but also for other devices, such as motor control units, that are equipped with programmable electronic trip units.
According to the present invention, this object is achieved by the fact that the hand-held terminal has a keypad for creating altered performance characteristics and for storing these altered performance characteristics in the electronic data memory, and the altered performance characteristics can be transmitted back out of the electronic data memory to the control unit of the electric device over the transmission means.
By using a hand-held terminal according to the present invention, when connected to the respective device, such as a circuit breaker or a motor control unit, the user is provided with a display showing which operating parameters and optionally which status values and diagnostic values are currently stored or programmed in the control unit. These parameters are entered into the electronic data memory of the hand-held terminal, where they are then available for processing. The parameters can be altered either with the existing connection to the control unit of the device or after being separated from the device. Due to the fact that the performance characteristics are stored in the hand-held terminal, it is possible in particular to set the trip units of multiple devices, e.g., multiple circuit breakers in a low-voltage switching station, at the same performance characteristics.
The application range of the hand-held terminal can be further expanded in an advantageous manner by also providing a variable program memory for storing an application program adapted to the performance characteristics to be processed. It is possible in this way to load the hand-held terminal with an application program adapted to different circuit breakers or motor control units so that the presentation, retrieval and modification of the performance characteristics can be processed in a well-defined manner.
To facilitate use of the various above-mentioned application programs for the hand-held terminal, an internal operating system for the microprocessor circuit may be provided with a test routine for the presence of an application program installed in the memory circuit of the control unit for the purpose of transfer to the program memory. This test routine can take place automatically as soon as the hand-held terminal has been connected to the respective device and activated.
Accordingly, a method of parameterization of performance characteristics of an electric device using a hand-held terminal described above, where the device has an electronic control unit with a memory circuit for the performance characteristics, may perform the following process steps:
connecting the hand-held terminal to the device,
reading out and displaying on the display device the performance characteristics stored in the memory circuit of the control unit,
storing the data corresponding to the performance characteristics thus read out under a selectable address in the data memory of the hand-held terminal,
altering at least one performance characteristic by entering at least one command on the hand-held terminal,
transmitting the altered performance characteristic to the control unit and acknowledgment of the completed transmission to the hand-held terminal, and
disconnecting the hand-held terminal from the device.
A modified method according to the present invention likewise serves to parameterize performance characteristics of an electric device using a hand-held terminal which also contains a variable program memory for storing an application program adapted to the performance characteristics to be processed.
The following process steps are provided:
connecting the hand-held terminal to the device,
reading out and displaying on the display device the performance characteristics stored in the memory circuit of the control unit,
storing the data corresponding to the performance characteristics thus read out under a selectable address in the data memory of the hand-held terminal,
disconnecting the hand-held terminal from the device,
altering the performance characteristics, optionally using the application program transmitted previously, and
reconnecting the hand-held terminal to the same device or an identical device and transmitting the altered performance characteristics to the electronic control unit of the device.